Liver flukes are parasitic worms which can infect human beings after eating raw or undercooked fresh water fish infested with the fluke. Parasites are organisms which receive nourishment from another organism where they live. In liver, there are varieties of such organisms, which are known to produce disease. Liver fluke is one of them.
Once the infested fish is ingested, liver fluke travels from intestine into the bile duct of liver. It matures and stays there for many years, as long as 20 to 30 years. Liver fluke infection in humans is more prevalent in South East Asia, China, Eastern Russia.People living along the river side are more susceptible because they tend to eat raw or undercooked fresh water fish.
Liver fluke produces chronic inflammation in the bile ducts which later on causes scarring and dilatation in the bile duct. Mature liver fluke releases thousands of eggs in a day. It is excreted from the bile duct and through the stool of an infected person. The vicious cycle continues after eating raw fish from fresh water. Liver fluke infection is comparatively rare in United States, although people who travel to infection borne areas in the world may suffer from it.
Liver Fluke Symptoms In Humans
People infected with liver fluke may remain symptomless for a long period of time. However, some patients may complain of symptoms such as abdominal pain, vomiting, nausea and diarrhea. Abdominal pain due to liver fluke is usually in the right upper zone of the abdomen. It is the site where liver is situated. The pain is quiet common in the early stage of infection, when liver fluke passes from intestine to the bile duct.
- Patient may also suffer from fever. In most cases, it occurs in the early stage of the infection. Fever is due to inflammation in the bile duct.
- Nausea, vomiting and diarrhea are three other symptoms that may be present in the early stage of infection. Later on patient may suffer from bile duct obstruction due to inflammatory changes in the duct.
- There is generalized fatigue experienced by the patient. Usually it occurs in the early stage of infection. Malaise and fatigue may also occur in the later stage when the liver begins to get damaged.
- Sometimes liver fluke infection can cause itching and hives on the body. This occurs when body’s immune system recognizes liver fluke as foreign body and produces allergic reaction.
- The chronic symptoms of liver fluke infection are loss of weight and appetite. If liver fluke remains undetected for years, it can produce irreparable damage to liver sometimes leading to cancer of bile duct.
Diagnosis And Treatment Of Human Liver Fluke
Liver fluke infection is often difficult to detect because many other diseases have similar symptoms. However, where liver fluke infection is widespread in certain parts of the world, screening test of stool is vital for its detection. Ova of liver fluke can be detected in stool. Besides, liver ultrasound is also an important test to detect liver fluke. MRI and CT scan can show dilatation of bile duct. Often the suspected patient gives history of eating raw fresh water fish.
Medical treatment of liver fluke consists of antihelmintic drugs. These drugs are prescribed and should be taken under medical supervision. The drug praziquantel is the treatment of choice for liver flukes. It is frequently prescribed by doctors. In some cases, where a part of the liver or gall bladder is damaged, it has to be removed surgically.
The best way to prevent liver fluke infection is to avoid eating raw fresh water fish.